A filling system and method for fully mechanized mining face passing through inclined gob roadway to improve coal quality

Abstract

The present invention discloses a filling system and method for fully mechanized mining face passing through inclined gob roadway to improve coal quality, which includes constructing a lower sealed wall and an upper sealed wall at the upper and lower ends of the inclined gob roadway respectively. An air vent and a measure hole are reserved at the top of the lower sealed wall, an exhaust port, a grouting hole and a mixed liquid grouting pipe are reserved at the top of the upper sealed wall, a conveying port is reserved at the bottom of the upper sealed wall, and a movable arc-shaped plastic chute with the upper end lapped with the belt conveyor for transporting coal is installed in the conveying port. The lower end enters the inclined gob roadway to fill the coal body. After the filling is completed, the movable arc-shaped plastic chute and the belt conveyor are withdrawn, and at the same time, the remaining space inside the inclined gob roadway is filled by grouting; after the inclined gob roadway is filled, the mixed liquid grouting pipe is withdrawn, and at the same time, all kinds of grouting pipelines are flushed with clear water. The present invention solves the technical problems of difficult roof management, poor safety and reliability, and influence on coal quality existing in the process of fully mechanized mining face passing through inclined gob roadway in existing coal mines.

Description

Technical Field

[0001] The present invention belongs to the field of coal mine empty road filling, and specifically relates to a filling system for a fully-mechanized mining face through an inclined empty road, which improves coal quality and quickly passes through an inclined empty road during the mining process of a fully-mechanized mining face in an underground coal mine, and is particularly suitable for an inclined empty road with an inclination angle of more than 25 degrees. The present invention also provides a method for filling an inclined empty road through a fully-mechanized mining face using the above system. Background Art

[0002] A problem was exposed during the construction of resource integration mines. A large number of abandoned empty tunnels existed within the scope of the mine field, and the layout of the old tunnels was intricate. Among them, the large-angle inclined empty tunnels had the greatest impact on the fully-mechanized mining face. Therefore, it is particularly important for the fully-mechanized mining face to pass through the inclined empty tunnel safely and quickly without affecting the coal quality. There are roughly two types of traditional practices for fully-mechanized mining faces to pass through inclined empty tunnels: one is to use anchor nets and single wooden pillars to strengthen the support strength in the empty tunnel to ensure that the working face passes through the inclined empty tunnel. This method has the disadvantages of cumbersome construction procedures, slow construction speed, poor safety and reliability, and difficult roof management; the second is to use conventional polymer materials to fill the empty tunnel. First, the inclined empty tunnel is sealed, and then the polymer grouting material is used to completely fill the inclined empty tunnel to achieve the smooth passage of the fully-mechanized mining face. This method can ensure that the working face passes through the inclined empty tunnel safely and quickly, but due to the large amount of grouting materials used in the empty tunnel, the grouting materials significantly affect the coal quality of the working face when the working face passes through the empty tunnel, and the economic benefits are poor. Summary of the invention

[0003] The present invention provides a filling system for a fully mechanized mining face passing through an inclined empty tunnel for improving coal quality, which is particularly suitable for an inclined empty tunnel with an inclination angle of more than 25°. It solves the technical problems of difficult roof management, poor safety and reliability, and influence on coal quality in the process of fully mechanized mining faces passing through inclined empty tunnels in existing underground coal mines.

[0004] The present invention solves the above technical problems through the following technical solutions:

[0005] A filling system for fully mechanized coal mining face passing through inclined gob roadway to improve coal quality, including an inclined gob roadway inside the coal mining face. At the bottom end inside the inclined gob roadway, there is a lower end sealed wall, and at the top end, there is an upper end sealed wall. At the top of the lower end sealed wall, there are an air vent and a measure hole. One end of the air vent and the measure hole communicates with the inclined gob roadway, and the other end leads to the outside. At the bottom of the upper end sealed wall, there is a delivery port. Along the roof of the inclined gob roadway at the top of the upper end sealed wall, there are an exhaust port and a grouting hole. Inside the delivery port, there is a mobile arc-shaped plastic chute for conveying coal. One end of the mobile arc-shaped plastic chute enters the inside of the inclined gob roadway for conveying coal body, and the other end is connected to a belt conveyor outside the inclined gob roadway. One end of the exhaust port and the grouting hole enters the inside of the inclined gob roadway, and the other end is connected to the outside. Inside the grouting hole, there is a mixed liquid grouting pipe, and the other end is connected to a filling pump station. After most of the gob roadway is filled with coal, the inclined gob roadway is grouted and filled using the mixed liquid grouting pipe arranged on the upper end sealed wall.

[0006] Further, the filling pump station consists of grouting filling materials, a slurry preparation device, a grouting pump, and a grouting pipeline. The grouting filling materials include Type A grouting materials, Type B grouting materials, a composite retarder, and a composite accelerator; the slurry preparation device includes at least four slurry mixing tanks, including at least two Type A slurry mixing tanks and at least two Type B slurry mixing tanks. Between the Type A slurry mixing tank and the grouting pump, they are connected by a Type A slurry inlet pipe. Between the Type B slurry mixing tank and the grouting pump 21, they are connected by a Type B slurry inlet pipe. The outlet end of the grouting pump is connected to a Type A slurry grouting pipe and a Type B slurry grouting pipe, and then connected to a slurry mixer. Among them, two Type A slurry mixing tanks and two Type B slurry mixing tanks are used alternately in pairs to achieve uninterrupted liquid supply; the grouting pump generally uses a double-fluid pump; the grouting pipeline uses a high-pressure rubber hose, and the pipe diameter is determined according to the grouting flow rate. The Type A slurry grouting pipe and the Type B slurry grouting pipe use high-pressure rubber hoses, and the mixed liquid grouting pipe generally uses seamless steel pipes. The volume of the mixing tank is 2m 3 。

[0007] Preferably, the slurry mixer is a tee pipe welded by steel pipes. The included angle between the two inlet ports is determined according to the slurry characteristics, generally 60°. The outlet port is located at the other end of the tee pipe, and the included angle with the inlet port is 150°. The steel pipe diameter is determined according to the grouting flow rate. After the single-component grouting pipes are mixed through the slurry mixer, they are transported to the inside of the gob roadway through the mixed liquid grouting pipe, filling the remaining space of the gob roadway, and forming a complete cemented body with the filled coal body in the gob roadway to jointly control the surrounding rock of the gob roadway.

[0008] Further, the mobile arc-shaped plastic chute 5 includes a semi-circular arc-shaped plastic chute. A support frame is provided at the bottom of the arc-shaped plastic chute. Tires are connected to both sides of the support frame through pin shafts. A parabolic opening is added at the bottom of the mobile arc-shaped plastic chute 5 to facilitate the filling of coal body. The mobile arc-shaped plastic chute is made of high-strength PVC plastic, with tires installed at the lower part. It is prepared in sections of 6 m in length and 1.5 m in height, with light weight and flexible movement, and can be continuously lengthened and connected.

[0009] Preferably, the inclination angle of the inclined empty roadway ≥ 25 0 。

[0010] Further, the exhaust port, grouting hole and mixed liquid grouting pipe are 280 - 320 mm away from the roof of the inclined empty roadway.

[0011] The present invention also provides a method for filling an inclined empty roadway in a fully mechanized coal mining face by using the above system, including the following steps: First stage: Build a lower sealed wall and an upper sealed wall at the upper and lower ends in the inclined empty roadway respectively. Discharge the gas inside the filled inclined empty roadway through the ventilation opening reserved at the top of the lower sealed wall and monitor the filling situation inside the empty roadway through the measure hole. The exhaust port, grouting hole and mixed liquid grouting pipe reserved between the top of the upper sealed wall and the roof of the inclined empty roadway ensure that the coal body filled in the first stage cannot block the grouting pipeline. Transport the coal to the mobile arc-shaped plastic chute through the belt conveyor for transporting coal. The arc-shaped plastic chute transports the coal into the inclined empty roadway through the delivery port. As the mobile arc-shaped plastic chute is continuously filled with coal body, the coal body at the bottom of the inclined empty roadway gradually fills up, and the mobile arc-shaped plastic chute continuously slides upward to fill the upper inclined empty roadway. This process is repeated until the first stage of filling the inclined empty roadway is completed, and the coal filling rate inside the empty roadway will reach 80% - 90% to improve the coal quality when the fully mechanized coal mining face passes through the empty roadway; Second stage: After the first stage is completed, withdraw the mobile arc-shaped plastic chute and the belt conveyor. At the same time, seal the ventilation opening on the lower sealed wall and the delivery port on the upper sealed wall inside the empty roadway. Connect the pre-reserved mixed liquid grouting pipe to the filling pump station in the idle roadway near the outside of the inclined empty roadway. The two A-type slurry mixing tanks and the two B-type slurry mixing tanks in the filling pump station are used alternately in pairs to achieve continuous supply of filling slurry. The A-type slurry mixing tank provides A-type slurry through the A-type slurry inlet pipe, and the B-type slurry mixing tank provides B-type slurry through the B-type slurry inlet pipe. Then, through the double-fluid pump to provide grouting pressure, it enters the inclined empty roadway through the A-type slurry grouting pipe, B-type slurry grouting pipe, slurry mixer and mixed liquid grouting pipe to fill the remaining 10% - 20% of the space inside the inclined empty roadway, ensure the complete fusion of the grouting liquid and the coal body, good roof contact, and form a unified colloid to ensure the stability of the surrounding rock inside the empty roadway; After the inclined empty roadway is filled, withdraw the mixed liquid grouting pipe. At the same time, seal the grouting hole and the exhaust port on the upper sealed wall and flush all kinds of grouting pipelines with clean water for future use.

[0012] Furthermore, after the coal body is mixed with the grouting material, according to different water-cement ratios and different filling ratios of the grouting material to the coal body, the ultimate strength of the mixed cemented body reaches above 0.5 MPa, meeting the requirements for filling the gob roadway, and at the same time, the coal quality requirements of the mined-out gob roadway can be significantly improved.

[0013] Furthermore, the water-cement ratio of the filling slurry is 6:1 - 10:1, and it can be adjusted on-site according to the setting time, setting strength, and filling effect.

[0014] Preferably, the grouting pump is generally a double-fluid pump, providing grouting pressure, and the slurry outlet pressure is 2.5 - 3.5 MPa.

[0015] The present invention is particularly applicable to inclined gob roadways with an inclination angle of more than 25°, which can effectively improve the safety and reliability of the fully mechanized mining face passing through the inclined gob roadway, significantly improve the coal quality of the fully mechanized mining face passing through the inclined gob roadway, and at the same time improve the construction technology and labor intensity of supporting the inclined gob roadway. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Now, the present invention will be further described with reference to the drawings, wherein:

[0017] Figure 1 is a schematic structural diagram of the coal body filling the inclined gob roadway of the present invention;

[0018] Figure 2 is a schematic structural diagram of the inclined gob roadway filled with high molecular grouting material of the present invention;

[0019] Figure 3 is a schematic structural diagram of the mobile arc-shaped plastic chute of the present invention;

[0020] Description of the reference numerals: 1, inclined gob roadway; 2, lower end sealed wall; 3, upper end sealed wall; 4, ventilation hole; 5, mobile arc-shaped plastic chute; 6, grouting pipe for Type A slurry; 7, grouting pipe for Type B slurry; 8, slurry mixer; 9, grouting pipe for the mixed liquid; 10, coal body; 11, grouting liquid; 12, grouting hole; 13, delivery port; 14, exhaust port; 15, measure hole; 16, belt conveyor; 17, stirring bucket for Type A slurry; 18, stirring bucket for Type B slurry; 19, inlet pipe for Type A slurry; 20, inlet pipe for Type B slurry; 21, grouting pump. DETAILED DESCRIPTION OF THE INVENTION

[0021] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0022] Embodiment 1

[0023] As Figures 1 to 3 shown, the filling system for the fully-mechanized coal mining face with inclined empty roadway to improve coal quality in this embodiment includes an inclined empty roadway 1 inside the coal mining face. At the bottom end inside the inclined empty roadway, there is a lower sealed wall 2, and at the top end, there is an upper sealed wall 3. At the top of the lower sealed wall 2, there are an air vent 4 and a measure hole 15. One end of the air vent 4 and the measure hole 15 communicates with the inclined empty roadway 1, and the other end leads to the outside. At the bottom of the upper sealed wall 3, there is a delivery port 13. Along the roof of the inclined empty roadway 1 at the top of the upper sealed wall 3, there are an exhaust port 14 and a grouting hole 12. Inside the delivery port 13, there is a mobile arc-shaped plastic chute 5 for transporting coal. One end of the mobile arc-shaped plastic chute 5 enters the inside of the inclined empty roadway 1 for transporting coal body 10, and the other end is connected to a belt conveyor 16 outside the inclined empty roadway 1. One end of the exhaust port 14 and the grouting hole 12 enters the inside of the inclined empty roadway 1, and the other end is connected to the outside. Inside the grouting hole 12, there is a mixed liquid grouting pipe 9, and the other end is connected to a filling pump station. After most of the empty roadway is filled with coal, the inclined empty roadway 1 is grouted and filled using the mixed liquid grouting pipe 9 provided in the upper sealed wall 3.

[0024] Furthermore, the filling pump station consists of grouting filling materials, a slurry preparation device, a grouting pump, and grouting pipelines. The grouting filling materials include Type A grouting materials, Type B grouting materials, a composite retarder, and a composite accelerator; the slurry preparation device includes at least four slurry mixing tanks, including at least two Type A slurry mixing tanks 17 and at least two Type B slurry mixing tanks 18. Between the Type A slurry mixing tank 17 and the grouting pump 21, they are connected through a Type A slurry inlet pipe 19. Between the Type B slurry mixing tank 18 and the grouting pump 21, they are connected through a Type B slurry inlet pipe 20. The outlet end of the grouting pump 21 is connected to a Type A slurry grouting pipe 6 and a Type B slurry grouting pipe 7, and then connected to a slurry mixer 8. Two of the Type A slurry mixing tanks 17 and two of the Type B slurry mixing tanks 18 are used alternately in pairs to achieve uninterrupted liquid supply; the grouting pump 21 generally uses a double-fluid pump; the grouting pipelines use high-pressure rubber hoses, and the pipe diameter is determined according to the grouting flow rate. The Type A slurry grouting pipe 6 and the Type B slurry grouting pipe 7 use high-pressure rubber hoses, and the mixed liquid grouting pipe 9 generally uses seamless steel pipes. The volume of the mixing tank is 2m 3 。

[0025] Preferably, the slurry mixer 8 is a tee pipe welded by steel pipes. The included angle between the two liquid inlets is determined according to the slurry characteristics, generally 60°, the liquid outlet is located at the other end of the tee pipe, and the included angle with the liquid inlet is 150°. The pipe diameter of the steel pipe is determined according to the grouting flow rate. After being mixed by the slurry mixer 8, the single-material grouting pipe is transported to the inside of the inclined empty roadway 1 through the mixed-liquid grouting pipe, fills the remaining space of the inclined empty roadway 1, and forms a complete cemented body with the filling coal body in the inclined empty roadway 1 to jointly control the surrounding rock of the inclined empty roadway 1.

[0026] Further, the mobile arc-shaped plastic chute 5 includes a semi-circular arc-shaped plastic chute, a support frame is arranged at the bottom of the arc-shaped plastic chute, tires are connected to both sides of the support frame through pin shafts, and an arc-shaped flat throwing port convenient for filling coal body is added at the bottom of the mobile arc-shaped plastic chute 5.

[0027] Preferably, the inclination angle of the inclined empty roadway 1 is ≥25 0 .

[0028] Preferably, the exhaust port 14, the grouting hole 12 and the mixed-liquid grouting pipe 9 are 280 mm away from the roof of the inclined empty roadway 1.

[0029] The present invention also provides a method for filling an inclined empty roadway in a fully mechanized coal mining face by using the above system, including the following steps:

[0030] The first stage: Build a lower end airtight wall 2 and an upper end airtight wall 3 at the upper and lower ends of the inclined empty roadway 1 respectively. Discharge the gas in the filled inclined empty roadway 1 and monitor the filling condition of the empty roadway through the ventilation port 4 reserved at the top of the lower end airtight wall 2. From the exhaust port 14 reserved between the top of the upper end airtight wall 3 and the roof of the inclined empty roadway 1, the grouting hole 12 and the mixed liquid grouting pipe 9, ensure that the coal body filled in the first stage cannot block the grouting pipeline. Transport the coal to the mobile arc-shaped plastic chute 5 through the belt conveyor 16 for transporting coal. The arc-shaped plastic chute transports the coal into the inclined empty roadway 1 through the delivery port 13. As the mobile arc-shaped plastic chute 5 is continuously filled with the coal body, the coal body at the bottom of the inclined empty roadway 1 gradually fills up, and the mobile arc-shaped plastic chute 5 continuously slides upward to fill the upper inclined empty roadway 1. Repeat this process until the first stage of filling the inclined empty roadway 1 is completed, and the coal filling rate inside the empty roadway will reach 80% - 90% to improve the coal quality when the fully mechanized mining face passes through the empty roadway. The second stage: After the first stage is completed, withdraw the mobile arc-shaped plastic chute 5 and the belt conveyor 16. At the same time, seal the ventilation port 4 on the lower end airtight wall 2 and the delivery port 13 on the upper end airtight wall 3 in the empty roadway. Connect the pre-reserved mixed liquid grouting pipe 9 to the filling pump station in the idle roadway near the outside of the inclined empty roadway 1. There are two Type A slurry mixing barrels 17 and two Type B slurry mixing barrels 18 in the filling pump station. The four mixing barrels are used alternately in pairs to achieve continuous supply of filling slurry. The Type A slurry mixing barrel 17 provides Type A slurry through the Type A slurry inlet pipe 19, and the Type B slurry mixing barrel 18 provides Type B slurry through the Type B slurry inlet pipe 20. Then, the double-fluid pump 21 provides the grouting pressure, and it enters the inclined empty roadway 1 through the Type A slurry grouting pipe 6, the Type B slurry grouting pipe 7, the slurry mixer 8 and the mixed liquid grouting pipe 9 to fill the remaining 10% - 20% of the space inside the inclined empty roadway 1, ensure that the grouting liquid 11 and the coal body 10 are completely fused, the roof contact is good, and a unified cemented body is formed to ensure the stability of the surrounding rock inside the empty roadway. After the inclined empty roadway 1 is filled, withdraw the mixed liquid grouting pipe 9. At the same time, seal the grouting hole 12 and the exhaust port 14 on the upper end airtight wall 3 and flush all kinds of grouting pipelines with clean water for future use.

[0031] Further, after the coal body is mixed with the grouting material, according to different water-cement ratios and different filling ratios of the grouting material and the coal body, the ultimate strength of the mixed cemented body reaches more than 0.5 MPa, meeting the requirements for filling the empty roadway.

[0032] Preferably, the water-cement ratio of the filling slurry is 6:1, and it can be adjusted on site according to the setting time, setting strength and filling effect.

[0033] Preferably, the grouting pump 21 is generally a double-fluid pump to provide grouting pressure, and the slurry outlet pressure is 2.5 MPa.

[0034] Example 2

[0035] As Figures 1 to 3 shown, the filling system for the fully mechanized coal mining face passing through the inclined empty roadway to improve coal quality in this embodiment includes an inclined empty roadway 1 inside the coal mining face. At the bottom end inside the inclined empty roadway, there is a lower end sealed wall 2, and at the top end, there is an upper end sealed wall 3. At the top of the lower end sealed wall 2, there are an air vent 4 and a measure hole 15. One end of the air vent 4 and the measure hole 15 communicates with the inclined empty roadway 1, and the other end leads to the outside. At the bottom of the upper end sealed wall 3, there is a conveying port 13. Along the roof of the inclined empty roadway 1 at the top of the upper end sealed wall 3, there are an exhaust port 14 and a grouting hole 12. Inside the conveying port 13, there is a mobile arc-shaped plastic chute 5 for conveying coal. One end of the mobile arc-shaped plastic chute 5 enters the inside of the inclined empty roadway 1 for conveying coal body 10, and the other end is connected to a belt conveyor 16 outside the inclined empty roadway 1. One end of the exhaust port 14 and the grouting hole 12 enters the inside of the inclined empty roadway 1, and the other end is connected to the outside. Inside the grouting hole 12, there is a mixed liquid grouting pipe 9, and the other end is connected to a filling pump station. After most of the empty roadway is filled with coal, the inclined empty roadway 1 is grouted and filled using the mixed liquid grouting pipe 9 provided on the upper end sealed wall 3.

[0036] Further, the filling pump station is composed of grouting filling materials, a slurry preparation device, a grouting pump, and grouting pipelines. The grouting filling materials include Type A grouting materials, Type B grouting materials, a composite retarder, and a composite accelerator; the slurry preparation device includes at least four slurry mixing tanks, including at least two Type A slurry mixing tanks 17 and at least two Type B slurry mixing tanks 18. Between the Type A slurry mixing tank 17 and the grouting pump 21, there is a connection through a Type A slurry inlet pipe 19. Between the Type B slurry mixing tank 18 and the grouting pump 21, there is a connection through a Type B slurry inlet pipe 20. The outlet end of the grouting pump 21 is connected to a Type A slurry grouting pipe 6 and a Type B slurry grouting pipe 7, and then connected to a slurry mixer 8. Among them, two Type A slurry mixing tanks 17 and two Type B slurry mixing tanks 18, the four mixing tanks are used alternately in pairs to achieve uninterrupted liquid supply; the grouting pump 21 generally uses a double-fluid pump; the grouting pipelines use high-pressure rubber hoses, and the pipe diameter is determined according to the grouting flow rate. The Type A slurry grouting pipe 6 and the Type B slurry grouting pipe 7 use high-pressure rubber hoses, and the mixed liquid grouting pipe 9 generally uses seamless steel pipes. The volume of the mixing tank is 2m 3 .

[0037] Preferably, the slurry mixer 8 is a tee pipe welded by steel pipes. The included angle between the two inlet pipes is determined according to the slurry characteristics, generally 60°. The outlet is located at the other end of the tee pipe, and the included angle with the inlet pipe is 150°. The steel pipe diameter is determined according to the grouting flow rate. After the single-component grouting pipes are mixed through the slurry mixer 8, they are transported to the inside of the inclined empty roadway 1 through the mixed liquid grouting pipe, filling the remaining space of the inclined empty roadway 1, and forming a complete cemented body with the filled coal body in the inclined empty roadway 1 to jointly control the surrounding rock of the inclined empty roadway 1.

[0038] Furthermore, the mobile arc-shaped plastic chute 5 includes a semi-circular arc-shaped plastic chute. A support frame is provided at the bottom of the arc-shaped plastic chute. Tires are connected to both sides of the support frame through pin shafts. A parabolic port for conveniently filling coal bodies is added at the bottom of the mobile arc-shaped plastic chute 5.

[0039] Preferably, the inclination angle of the inclined empty roadway 1 is ≥25 0 .

[0040] Preferably, the exhaust port 14, the grouting hole 12 and the mixed liquid grouting pipe 9 are 300 mm away from the roof of the inclined empty roadway 1.

[0041] The present invention also provides a method for filling an inclined empty roadway in a fully mechanized coal mining face by using the above system, including the following steps:

[0042] The first stage: At the upper and lower ends of the inclined empty roadway 1, a lower sealed wall 2 and an upper sealed wall 3 are respectively constructed. The gas in the filled inclined empty roadway is discharged through the ventilation opening 4 reserved at the top of the lower sealed wall 2, and the measure hole 15 monitors the filling situation inside the empty roadway. The exhaust port 14, grouting hole 12 and mixed liquid grouting pipe 9 reserved between the top of the upper sealed wall 3 and the roof of the inclined empty roadway 1 ensure that the coal body filled in the first stage cannot block the grouting pipeline. The coal is transported to the mobile arc-shaped plastic chute 5 through the belt conveyor 16 for transporting coal. The arc-shaped plastic chute transports coal into the inclined empty roadway 1 through the conveying port 13. As the mobile arc-shaped plastic chute 5 is continuously filled with coal body, the coal body at the bottom of the inclined empty roadway 1 gradually fills up, and the mobile arc-shaped plastic chute 5 continuously slides upward to fill the upper inclined empty roadway 1. This process is repeated until the first stage of filling of the inclined empty roadway 1 is completed, and the coal filling rate inside the empty roadway will reach 80% - 90% to improve the coal quality when the fully mechanized mining face passes through the empty roadway. The second stage: After the first stage is completed, the mobile arc-shaped plastic chute 5 and the belt conveyor 16 are withdrawn. At the same time, the ventilation opening 4 on the lower sealed wall 2 and the conveying port 13 on the upper sealed wall 3 inside the empty roadway are closed. The reserved mixed liquid grouting pipe 9 is connected to the filling pump station in the idle roadway near the outside of the inclined empty roadway 1. There are two type A slurry mixing tanks 17 and two type B slurry mixing tanks 18 in the filling pump station. The four mixing tanks are used alternately in pairs to achieve uninterrupted supply of filling slurry. The type A slurry mixing tank 17 provides type A slurry through the type A slurry inlet pipe 19, and the type B slurry mixing tank 18 provides type B slurry through the type B slurry inlet pipe 20. Then, the double-fluid pump 21 provides the grouting pressure, and it enters the inclined empty roadway 1 through the type A slurry grouting pipe 6, type B slurry grouting pipe 7, slurry mixer 8 and mixed liquid grouting pipe 9 to fill the remaining 10% - 20% of the space inside the inclined empty roadway 1, ensuring that the grouting liquid 11 and the coal body 10 are completely fused and the roof contact is good, forming a unified cemented body to ensure the stability of the surrounding rock inside the empty roadway. After the filling of the inclined empty roadway 1 is completed, the mixed liquid grouting pipe 9 is withdrawn. At the same time, the grouting hole 12 and the exhaust port 14 on the upper sealed wall 3 are closed and all grouting pipelines are flushed with clean water for future use.

[0043] Furthermore, after the coal body is mixed with the grouting material, according to different water-cement ratios and different filling ratios of the grouting material and the coal body, the ultimate strength of the mixed cemented body reaches above 0.5 MPa, meeting the requirements for filling the empty roadway.

[0044] Preferably, the water-cement ratio of the filling slurry is 8:1, and it can be adjusted on-site according to the setting time, setting strength and filling effect.

[0045] Preferably, the grouting pump 21 is generally a double-fluid pump to provide grouting pressure, and the slurry outlet pressure is 3 MPa.

[0046] Example 3

[0047] As Figures 1 to 3 shown, the filling system for a fully mechanized coal mining face passing through an inclined gob to improve coal quality in this embodiment includes an inclined gob 1 inside the coal mining face. At the bottom end inside the inclined gob, there is a lower sealed wall 2, and at the top end, there is an upper sealed wall 3. An air vent 4 and a measure hole 15 are provided at the top of the lower sealed wall 2. One end of the air vent 4 and the measure hole 15 communicates with the inclined gob 1, and the other end leads to the outside. A delivery port 13 is provided at the bottom of the upper sealed wall 3. An exhaust port 14 and a grouting hole 12 are arranged along the roof of the inclined gob 1 at the top of the upper sealed wall 3. A mobile arc-shaped plastic chute 5 for transporting coal is arranged inside the delivery port 13. One end of the mobile arc-shaped plastic chute 5 enters the inside of the inclined gob 1 for transporting coal body 10, and the other end is connected to a belt conveyor 16 outside the inclined gob 1. One end of the exhaust port 14 and the grouting hole 12 enters the inside of the inclined gob 1, and the other end is connected to the outside. A mixed liquid grouting pipe 9 is arranged inside the grouting hole 12, and the other end is connected to a filling pump station. After most of the gob is filled with coal, the inclined gob 1 is grouted and filled using the mixed liquid grouting pipe 9 provided in the upper sealed wall 3.

[0048] Further, the filling pump station is composed of grouting filling materials, a slurry preparation device, a grouting pump, and grouting pipelines. The grouting filling materials include Type A grouting materials, Type B grouting materials, a composite retarder, and a composite accelerator; the slurry preparation device includes at least four slurry mixing tanks, including at least two Type A slurry mixing tanks 17 and at least two Type B slurry mixing tanks 18. A Type A slurry inlet pipe 19 is connected between the Type A slurry mixing tank 17 and the grouting pump 21, and a Type B slurry inlet pipe 20 is connected between the Type B slurry mixing tank 18 and the grouting pump 21. The outlet end of the grouting pump 21 is connected to a Type A slurry grouting pipe 6 and a Type B slurry grouting pipe 7, and then connected to a slurry mixer 8. Two of the Type A slurry mixing tanks 17 and two of the Type B slurry mixing tanks 18 are used alternately in pairs to achieve uninterrupted liquid supply; the grouting pump 21 generally uses a double-fluid pump; the grouting pipelines use high-pressure rubber hoses, and the pipe diameter is determined according to the grouting flow rate. The Type A slurry grouting pipe 6 and the Type B slurry grouting pipe 7 use high-pressure rubber hoses, and the mixed liquid grouting pipe 9 generally uses seamless steel pipes. The volume of the mixing tank is 2m 3 .

[0049] Preferably, the slurry mixer 8 is a tee pipe welded by steel pipes. The included angle between the two inlet pipes is determined according to the slurry characteristics, generally 60°, and the outlet is located at the other end of the tee pipe, with an included angle of 150° with the inlet pipe. The steel pipe diameter is determined according to the grouting flow rate. After the single-material grouting pipes are mixed through the slurry mixer 8, they are transported to the inside of the inclined gob 1 through the mixed liquid grouting pipe, filling the remaining space of the inclined gob 1, and forming a complete cemented body with the filled coal body in the inclined gob 1 to jointly control the surrounding rock of the inclined gob 1.

[0050] Furthermore, the mobile arc-shaped plastic chute 5 includes a semi-circular arc-shaped plastic chute. A support frame is provided at the bottom of the arc-shaped plastic chute. Tires are connected to both sides of the support frame through pin shafts. A parabolic opening for conveniently filling coal bodies is added at the bottom of the mobile arc-shaped plastic chute 5.

[0051] Preferably, the inclination angle of the inclined empty roadway 1 is ≥25 0 .

[0052] Preferably, the exhaust port 14, the grouting hole 12, and the mixed liquid grouting pipe 9 are 320 mm away from the roof of the inclined empty roadway 1.

[0053] The present invention also provides a method for filling an inclined empty roadway in a fully mechanized coal mining face by using the above system, which includes the following steps:

[0054] The first stage: Build a lower sealed wall 2 and an upper sealed wall 3 at the upper and lower ends of the inclined empty roadway 1 respectively. Discharge the gas in the filled inclined empty roadway through the ventilation opening 4 reserved at the top of the lower sealed wall 2, and monitor the filling situation inside the empty roadway through the measure hole 15. From the exhaust port 14 reserved between the top of the upper sealed wall 3 and the roof of the inclined empty roadway 1, the grouting hole 12 and the mixed liquid grouting pipe 9, ensure that the coal body filled in the first stage cannot block the grouting pipeline. Convey the coal to the mobile arc-shaped plastic chute 5 through the belt conveyor 16 for transporting coal. The arc-shaped plastic chute conveys coal into the inclined empty roadway 1 through the conveying port 13. As the mobile arc-shaped plastic chute 5 is continuously filled with coal body, the coal body at the bottom of the inclined empty roadway 1 gradually fills up, and the mobile arc-shaped plastic chute 5 continuously slides upward to fill the upper inclined empty roadway 1. Repeat this process until the inclined empty roadway 1 completes the first stage of filling, and the coal filling rate inside the empty roadway will reach 80% - 90% to improve the coal quality when the fully mechanized mining face passes through the empty roadway. The second stage: After the first stage is completed, withdraw the mobile arc-shaped plastic chute 5 and the belt conveyor 16. At the same time, seal the ventilation opening 4 on the lower sealed wall 2 and the conveying port 13 on the upper sealed wall 3 inside the empty roadway. Connect the pre-reserved mixed liquid grouting pipe 9 to the filling pump station in the idle roadway near the outside of the inclined empty roadway 1. There are two Type A slurry mixing tanks 17 and two Type B slurry mixing tanks 18 in the filling pump station. The four mixing tanks are used alternately in pairs to achieve continuous supply of filling slurry. The Type A slurry mixing tank 17 provides Type A slurry through the Type A slurry inlet pipe 19, and the Type B slurry mixing tank 18 provides Type B slurry through the Type B slurry inlet pipe 20. Then, through the double-fluid pump 21 to provide grouting pressure, it enters the inclined empty roadway 1 through the Type A slurry grouting pipe 6, the Type B slurry grouting pipe 7, the slurry mixer 8 and the mixed liquid grouting pipe 9 to fill the remaining 10% - 20% of the space inside the inclined empty roadway 1, ensure that the grouting liquid 11 is completely integrated with the coal body 10, the roof contact is good, and form a unified cemented body to ensure the stability of the surrounding rock inside the empty roadway. After the inclined empty roadway 1 is filled, withdraw the mixed liquid grouting pipe 9. At the same time, seal the grouting hole 12 and the exhaust port 14 on the upper sealed wall 3 and flush all kinds of grouting pipelines with clean water for the next use.

[0055] Further, after the coal body is mixed with the grouting material, according to different water-cement ratios and different filling ratios of the grouting material and the coal body, the ultimate strength of the mixed cemented body reaches more than 0.5 MPa, meeting the requirements for filling the empty roadway.

[0056] Preferably, the water-cement ratio of the filling slurry is 10:1, and it can be adjusted on-site according to the setting time, setting strength and filling effect.

[0057] Preferably, the grouting pump 21 is generally a double-fluid pump to provide grouting pressure, and the slurry outlet pressure is 3.5 MPa.

[0058] It should be noted that, in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.

[0059] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A filling method for fully mechanized mining face passing through inclined gob roadway to improve coal quality, characterized in that An inclined empty roadway (1) included inside a coal mining face, with a lower end airtight wall (2) provided at the bottom inside the inclined empty roadway, and an upper end airtight wall (3) provided at the top. An air vent (4) and a measure hole (15) are arranged at the top of the lower end airtight wall (2). One end of the air vent (4) and the measure hole (15) communicates with the inclined empty roadway (1), and the other end leads to the outside. A conveying port (13) is provided at the bottom of the upper end airtight wall (3). An exhaust port (14) and a grouting hole (12) are arranged along the roof of the inclined empty roadway (1) at the top of the upper end airtight wall (3). A mobile arc-shaped plastic chute (5) for conveying coal is arranged inside the conveying port (13). One end of the mobile arc-shaped plastic chute (5) enters the inside of the inclined empty roadway (1) for conveying coal body (10), and the other end is connected to a belt conveyor (16) outside the inclined empty roadway (1). One end of the exhaust port (14) and the grouting hole (12) enters the inside of the inclined empty roadway (1), and the other end is connected to the outside. A mixed liquid grouting pipe (9) is arranged inside the grouting hole (12), and the other end is connected to a filling pump station; The filling pump station is composed of grouting filling materials, a slurry preparation device, a grouting pump, and grouting pipelines. The grouting filling materials include Type A grouting materials, Type B grouting materials, a composite retarder, and a composite accelerator; the slurry preparation device includes at least four slurry mixing tanks, including at least two Type A slurry mixing tanks (17) and at least two Type B slurry mixing tanks (18). A Type A slurry inlet pipe (19) is connected between the Type A slurry mixing tank (17) and the grouting pump (21), and a Type B slurry inlet pipe (20) is connected between the Type B slurry mixing tank (18) and the grouting pump (21). The outlet end of the grouting pump (21) is connected to a Type A slurry grouting pipe (6) and a Type B slurry grouting pipe (7), and then connected to a slurry mixer (8); According to the following steps: The first stage: Build the lower end airtight wall (2) and the upper end airtight wall (3) at the upper and lower ends inside the inclined empty roadway (1) respectively. Discharge the gas inside the filled inclined empty roadway (1) and monitor the filling situation of the empty roadway through the measure hole (15) through the air vent (4) reserved at the top of the lower end airtight wall (2). Ensure that the coal body filled in the first stage cannot block the grouting pipeline through the exhaust port (14), the grouting hole (12), and the mixed liquid grouting pipe (9) reserved between the top of the upper end airtight wall (3) and the roof of the inclined empty roadway (1). Convey the coal to the mobile arc-shaped plastic chute (5) through the belt conveyor (16) for transporting coal. The arc-shaped plastic chute conveys coal into the inclined empty roadway (1) through the conveying port (13). As the mobile arc-shaped plastic chute (5) is continuously filled with coal body, the coal body at the bottom of the inclined empty roadway (1) gradually piles up, and the mobile arc-shaped plastic chute (5) continuously slides upward to fill the upper inclined empty roadway (1). Repeat this process until the first stage of filling of the inclined empty roadway (1) is completed, and the coal filling rate inside the empty roadway will reach 80% - 90% to improve the coal quality when the fully mechanized coal mining face passes through the empty roadway; Second stage: After the first stage is completed, remove the mobile arc-shaped plastic chute (5) and the belt conveyor (16). At the same time, seal the ventilation opening (4) on the lower end airtight wall (2) and the conveying opening (13) on the upper end airtight wall (3) in the empty roadway. Connect the pre-reserved mixed liquid grouting pipe (9) to the filling pump station in the idle roadway near the outside of the inclined empty roadway (1). In the filling pump station, there are two Type A slurry mixing tanks (17) and two Type B slurry mixing tanks (18). The four mixing tanks are used alternately in pairs to achieve uninterrupted supply of filling slurry. The Type A slurry mixing tank (17) provides Type A slurry through the Type A slurry inlet pipe (19), and the Type B slurry mixing tank (18) provides Type B slurry through the Type B slurry inlet pipe (20). Then, the double-fluid pump (21) provides grouting pressure, and the slurry enters the inclined empty roadway (1) through the Type A slurry grouting pipe (6), Type B slurry grouting pipe (7), slurry mixer (8) and mixed liquid grouting pipe (9) to fill 10% - 20% of the remaining space inside the inclined empty roadway (1), ensuring that the grouting liquid (11) is completely integrated with the coal body (10), with good roof contact, forming a unified cemented body to ensure the stability of the surrounding rock inside the empty roadway; after the inclined empty roadway (1) is filled, remove the mixed liquid grouting pipe (9). At the same time, seal the grouting hole (12) and exhaust port (14) on the upper end airtight wall (3) and rinse all kinds of grouting pipelines with clean water for future use.

2. The filling method for fully mechanized mining face passing through inclined gob roadway to improve coal quality according to claim 1, characterized in that The slurry mixer (8) is a three-way pipe welded by steel pipes.

3. The filling method for fully mechanized mining face passing through inclined empty roadway to improve coal quality according to claim 1, characterized in that, The mobile arc-shaped plastic chute (5) includes a semi-circular arc-shaped plastic chute. A support frame is provided at the bottom of the arc-shaped plastic chute. Tires are connected to both sides of the support frame through pin shafts. A parabolic opening for facilitating the filling of coal body is added at the bottom of the mobile arc-shaped plastic chute (5).

4. A filling method for fully-mechanized mining face passing through inclined gob roadway to improve coal quality according to claim 1, characterized in that, The dip angle of the inclined gob roadway (1) ≥ 25 0 .

5. A backfilling method for fully mechanized mining face passing through inclined gob roadway to improve coal quality according to claim 3, characterized in that, The exhaust port (14), grouting hole (12) and mixed liquid grouting pipe (9) are 280 - 320 mm away from the roof of the inclined empty roadway (1).

6. A filling method for a fully mechanized mining face passing through an inclined empty roadway to improve coal quality according to claim 1, characterized in that, After the coal body is mixed with the grouting material, according to different water-cement ratios and different filling ratios of the grouting material to the coal body, the ultimate strength of the mixed cemented body reaches above 0.5 MPa, meeting the requirements for filling the empty roadway.

7. A filling method for a fully mechanized coal mining face passing through an inclined empty roadway to improve coal quality according to claim 1, characterized in that The water-cement ratio of the filling slurry is 6:1 - 10:

1.

8. The filling method for fully-mechanized mining face passing through inclined gob roadway to improve coal quality according to claim 1, characterized in that, The double-fluid pump (21) provides grouting pressure, and the slurry outlet pressure is 2.5 - 3.5 MPa.

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